Question

Suppose 40 percent of Senegal's population speaks Wolof as a first language. If that's about 5 million people, approximately what is Senegal's population? Express your answer in scientific notation

Answer 1

5 million = 5*10^6

40% * x = 5*10^6

x = (5*10^6)/0.4 = (5/0.4)*10^6 = 12.5 * 10^6 = 1.25 *10^7

Answer 2

Let the total population of Senegal be represented by the letter "x".

Now, we are given that 40% of x=5 million.

This can be rewritten as:
`(40)/(100)x=5000000`

`0.4x=5000000`

`x=(5000000)/(0.4) =12500000`

This can be represented in the scientific notation as:

`x=1.25* 10^(7)`

Thus Senegal's population in scientific notation is
`1.25* 10^(7)`